Process Safety and Environmental Protection, Vol.146, 118-125, 2021
The use of second-hand items based on delay time modelling
In view of the increasing tendency to make use of second-hand items, we present a schematic framework that models the possible reuse of an item considering its defective condition, based on the delay time concept. A parallel between the traditional delay time model for single-component systems and the proposed model for the reuse of items is provided in order to emphasize our contribution. In general terms, our model may be applied to any component that wears out over time and that may be replaced by a new one or by a refurbished item. The results show reductions in the order of 36.7 % in the expected cost over an inspection cycle. Also, results indicate that the higher the level of reused items, the lower the expected cost, which suggests the reuse of items can serve not only to generate less severe environmental impacts but also to generate economic benefits. Finally, the main contribution of this paper is an inspection policy that encompasses the level of reused items, in a way that links the condition of the item with savings made by recycling it. The findings presented here reinforce the need to use recycled items, since apart from this leading to greater sustainability in the use of natural resources, some conditions may well result in cost savings. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.